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Abstract:

A detonator formed entirely from a plurality of discrete segments of an
insensitive energetic composition, each of the segments employed in the
detonator being compacted at different pressures from powder and/or
granules of insensitive energetic composition so as to form an energetic
train which sequences detonation of the individual segments. Initiation
of a main charge can only be effected when a last segment in the
detonation train is initiated. Detonation starts with a first segment in
the detonation train which is produced under the lowest compaction
pressure, and then detonation progresses to a last segment compacted
under a higher compaction pressure. The first segment can be detonated by
a safety fuse or detonating cord, and the last segment can only be
detonated by the next to the last segment in the detonation train.

Claims:

1. In an explosive pyrotechnic device, military munition, or rocket
comprising: (a) a main charge of explosive or propellant formed primarily
of an insensitive energetic composition; (b) a detonator to trigger or
initiate the main charge, said detonator being primarily formed of an
insensitive energetic composition of lead azide, and lead styphnate; (c)
a fuse, shock cord or primer to trigger or initiate the detonator; the
improvement comprising: a detonator formed entirely from a plurality of
discrete segments of an insensitive energetic composition, each segment
being formed by compacting under pressure powdered and/or granular
insensitive energetic composition having a sensitivity to detonation
which decreases with an amount of compressive force applied in compaction
of the powder and/or granules of the insensitive energetic composition,
said plurality of discrete segments comprising at least a first and last
discrete segment of compacted insensitive energetic composition, each
having been formed under different compaction pressures: said first
segment being compacted under a compaction pressure low enough that
ignition of the fuse or primer will effect detonation of said first
segment without detonating either the main charge or any other segment of
the insensitive energetic composition, said last segment being subjected
to a compaction pressure high enough that only ignition of the next to
the last segment will initiate detonation of said last segment, which in
turn initiates detonation of said main charge, thereby eliminating the
need in the detonator for lead azide and lead styphnate.

2. The explosive pyrotechnic device, military munition or rocket of claim
1, wherein the plurality of segments employed in the detonator are each
compacted under different pressures from powder and/or granules of
insensitive energetic composition so as to form an energetic train which
sequences detonation of the individual segments starting with the first
segment produced under the lowest compaction pressure and then
progressing to segments compacted under higher compaction pressures.

3. The explosive pyrotechnic device, military munition or rocket of claim
1, wherein said detonators are formed from granules and/or powdered RDX.

4. The explosive pyrotechnic device, military munition or rocket of claim
1, wherein said detonators are formed from granules and/or powdered HMX.

5. The explosive pyrotechnic device, military munition or rocket of claim
3, wherein the first segment is compacted under a pressure of about 2,000
psi.

6. The explosive pyrotechnic device, military munition or rocket of claim
3, wherein the last segment is compacted under a pressure of about 4,000
psi.

7. The explosive pyrotechnic device, military munition or rocket of claim
3, wherein the first segment is compacted under a pressure of about 2,000
psi and the last segment is compacted under a pressure of about 4,000
psi.

9. The explosive pyrotechnic device, military munition or rocket of claim
1, wherein the pyrotechnic device having an explosive charge is used in
rock blasting, mining, and/or oil drilling.

10. A detonator formed entirely from a plurality of discrete segments of
an insensitive energetic composition, each segment being formed by
compacting under pressure powdered and/or granular insensitive energetic
composition having a sensitivity to detonation which decreases with a
decrease in an amount of compressive force applied in compaction of the
powder and/or granules of the insensitive energetic composition, said
plurality of discrete segments comprising at least a first and last
discrete segments of compacted insensitive energetic composition, each
having been formed under different compaction pressures.

11. The detonator of claim 10, wherein said first segment is compacted
under a compaction pressure low enough that ignition of the fuse or
primer will effect detonation of said first segment, without detonating
either the main charge or any other segment of insensitive energetic
composition.

12. The detonator of claim 10, wherein said last segment is subjected to
a compaction pressure high enough that only ignition of a next to the
last segment will initiate detonation of said last segment, which in turn
causes detonation of said main charge.

13. The detonator of claim 10, wherein the plurality of segments employed
in the detonator are each compacted at different pressures from powder
and/or granules of insensitive energetic composition, so as to form an
energetic train which sequences detonation of the individual segments
starting with the segment produced under the lowest compaction pressure
and then progressing to segments compacted under higher compaction
pressures.

14. The detonator of claim 10, wherein said first segment is compacted
under a compaction pressure low enough that ignition of the fuze or
primer will effect detonation of said first segment without detonating
either the main charge or any other segment of the detonation train, said
last segment being subjected to a compaction pressure high enough that
only ignition of a next to the last segment will initiate detonation of
said last segment, which in turn causes detonation of said main charge.

15. The detonator of claim 14, wherein the plurality of segments employed
in the detonator are each compacted at different pressures from powder
and/or granules of insensitive energetic composition so as to form an
energetic train which sequences detonation of the individual segments
starting with the segment produced under the lowest compaction pressure
and then progresses to segments compacted under increasingly higher
compaction pressures.

16. The detonator of claim 10, wherein said detonator is formed from
granules and/or powdered RDX.

17. The detonator of claim 16, wherein the first segment of RDX is
compacted under a pressure of about 2,000 psi, and the last segment of
RDX is compacted under a pressure of about 4,000 psi.

18. The detonator of claim 10, wherein said detonator is formed from
granules and/or powdered HMX.

19. The detonator of claim 10, which is employed in a pyrotechnic device
selected from the group consisting of hand grenades, bombs, rockets,
mortars, mines, satchel charges, bazooka shells, artillery shells,
destructor assemblies, and ammunition.

20. A detonator formed entirely from a plurality of discrete segments of
an insensitive energetic composition, each of said segments employed in
the detonator being compacted at different pressures from powder and/or
granules of insensitive energetic composition so as to form an energetic
train which sequences detonation of the individual segments, starting
with a first segment in the detonation train produced under a lowest
compaction pressure, and then progressing to segments compacted under
higher compaction pressures until a last segment in the detonation train
is initiated by a next to the last segment, and a main charge is
initiated only by detonation of the last segment.

Description:

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates in general to explosive devices
including pyrotechnic devices, munitions, and rockets which utilize a
detonator assembly and, more particularly, to a detonator formed entirely
from insensitive energetic compositions, and to a method of making same.

[0004] 2. Background Art

[0005] Under their normal condition of use, modern munitions are both
effective and relatively safe, and they are unlikely to explode or burn
spontaneously despite the fact that they are composed primarily of
energetic material. The energetic materials, i.e., high explosives, gun
propellants, rocket propellants, etc. found in munitions of all types are
sensitive to heat and to mechanical shock. Consequently, they can be
triggered by fire or by impact with bullets or fragments.

[0006] A range of energetic materials can be used in low-risk munitions:
explosives and propellants less vulnerable than their predecessors to
both slow and rapid heating (cook off) and to impact by bullets or
fragments of exploding shells. For gun propellants, the single, double
and triple base formulations now in service can be replaced by others
based on components that are more energetic but less sensitive. In the
case of warheads, efforts are being made to replace explosives such as
TNT, which is very sensitive to heat and shock, with a more stable
plastic-bonded explosives which are better able to withstand adverse
conditions. These new explosives and gun propellants are made primarily
with energetic crystals such as RDX and HMX, contained in new energetic
binders and plasticizers.

[0007] An insensitive munition (IM) is one that will not detonate under
any conditions other than its intended mission to destroy a target. If it
is struck by fragments from an exploding shell or struck by a bullet, it
will not detonate. Also, it will not detonate if it is in close proximity
to a target that is struck. Further, in extreme temperatures, the
munition will only burn without creating/generating an explosion or a
detonation.

[0008] To reduce the chance of accidental explosions or fires, the U.S.
military is interested in replacing existing main charge explosives with
newer more insensitive explosives such as PBXN-103 and PBXN-109. Existing
booster explosives and fuses have insufficient energy output to reliably
initiate the new insensitive main charge explosives. The existing
Department of Defense inventory of fuses and booster explosives is very
large and cannot be replaced without considerable cost. What is needed is
an inexpensive method of reliably initiating the new, more insensitive
main charge explosives while at the same time reducing the chance of an
accidental initiation of a fuse or detonator system.

[0009] The U.S. Department of Defense is interested in reducing weapon
vulnerability and improving weapon safety in extreme and abnormal
environments. Insensitive munitions are one way to achieve these goals. A
fuse train is needed that will ignite these insensitive munitions at
extremes of temperature, but will not compromise the insensitivity of HE
main charge fill to external threats (U.S. Pat. No. 5,275,106).

[0010] U.S. Pat. No. 5,567,912 discloses that insensitive munitions are
prepared by making an energetic composition, processing the composition
into intermediate shapes and fabricating an article from the intermediate
shape. The article may itself be directed to military use such as a
munition or ammunition, and it may also be directed to civilian uses such
as demolition charges. In these applications, the explosive is formed
into an article that will have blasting effects when exploded. The
explosive article is assembled along with other items, such as
propellants, fuses, guidance systems, etc. into the munition. The
munition can be a small caliber bullet, a large caliber shell, a warhead,
a rocket, a bomb, a mortar, a hand grenade, torpedo, mine or similar
device. It can be loaded into a weapon such as an artillery piece, a tank
or armored vehicle.

[0011] U.S. Pat. No. 5,567,912 also discloses that an insensitive munition
may be formed from crystalline heterocyclic nitramines HMX and RDX. These
materials have very high energy densities and are well known in the
field. They have been used in ammunitions and munitions for over sixty
years and a very large body of data have been developed for their
manufacture and safe use in munitions in both propellants and explosives.

[0012] HMX and RDX have been type classified and described with military
specifications in most countries in the world. HMX has a higher energy
density than RDX. These materials are available in the form of fine
powders.

A conventional explosive is illustrated in FIG. 1 and includes a
conventional melt poured or pressed main charge shown generally at 1
which may or may not be formed from an insensitive munition. Detonation
of the main charge is effected by means of a detonator 3. The detonator
is initiated by a fuse 5 in the form of a shock cord. The shock cord 5 in
turn initiates detonator 3, which includes lead styphnate 7, which in
turn initiates an adjacent charge of lead azide 9, which in turn
initiates a charge 11 of RDX. The detonator energetics are
Non-Insensitive Munitions (IM) compliant due to the presence of lead
styphnate 7 and lead azide 9. In the embodiment shown in FIG. 1,
detonator 3 is initiated via shock cord 5 or other fuse means, which
starts the energetic train from lead styphnate 7 to lead azide 9 to RDX
11, which finally has the shock energy and velocity to detonate main
energetic 1.

[0013] Even though a main charge in a pyrotechnic device may be an
insensitive energetic, detonators employing lead azide and lead styphnate
are in fact very sensitive to shock, friction and static discharges, even
from the human body. Both of these lead compounds have a very high
explosive detonation velocity of about 5200 meters per second. Moreover,
lead azide has an auto ignition of 350° C., and lead styphnate has
an auto ignition of 330° C. In addition, as with other lead
containing compounds, both lead styphnate and lead azide are inherently
toxic to humans if ingested, i.e., they can cause heavy metal poisoning.

[0014] In addition, lead styphnate and lead azide are highly sensitive and
are usually handled and stored under water in insulated rubber
containers. They will explode after a fall of no more than about six
inches or in the presence of a static discharge of 7 millijoules. These
properties make these materials highly dangerous and expensive to use in
manufacturing pyrotechnic devices. For these reasons, a detonator which
is effective without the use of lead azide, lead styphnate, or any other
highly sensitive explosive material is needed in pyrotechnic devices,
especially those having a main charge of insensitive energetic.

[0015] Current detonator designs used in many types of munitions are also
illustrated in FIG. 2. These detonators in FIG. 2 have been available for
many years and represent the current military and commercial standard.
There are several designs that are fabricated and include M2, M10 and M14
detonators. These are typical detonators units that have a wide
industrial and commercial usage. In the design in FIG. 2 shown generally
at 13 is a shock cord 15 which initiates detonation of the lead styphnate
17, which in turn detonates the adjacent lead azide 19, which in turn
detonates an RDX charge 21, which in turn detonates the main charge (not
shown).

[0016] The current design in FIG. 3 of hand grenades shown generally at 23
includes a fuse assembly which is similar to a detonator assembly as
previously described above, except the shock cord is replaced with a
primer 25 and delay mix 27. In this conventional hand grenade 23, the
handle 29 is pulled away from the body 31 of the grenade 23 to initiate
detonation of the primer 25. The primer then initiates detonation of
delay mix 27, which in turn initiates detonation of lead styphnate 33,
which in turn initiates detonation of lead azide 35, which in turn
detonates an adjacent RDX charge 37. It is the RDX charge 37 which
initiates detonation of the main energetic filling 39 in body 31 of hand
grenade 23.

[0017] The RDX charge in current detonators is formed by compaction of the
powder or granular RDX. This process is carried out by forcing powdered
or granular RDX into a die cavity by means of a mandrel to compress and
compact the RDX powder.

[0018] It is therefore an object of the present invention to provide a
detonator for insensitive high explosives.

[0019] It is a further object of the present invention to provide a fuse
train for insensitive high explosives which is free of either lead azide
or lead styphnate.

[0020] It is a still further object of the present invention to provide an
insensitive fuse train capable of initiating insensitive munitions at
extreme temperatures and without the use of a sensitive high explosive
like lead azide and/or lead styphnate.

[0021] It is further another object of the present invention to provide
insensitive munitions which cannot be initiated by various stimuli
including cook-off (high temperatures), bullet/fragment impacts, and
shape charge impacts.

[0022] In view of the aforementioned drawbacks associated with the use in
detonators of lead azide and lead staphynate, there remains a need in the
art for an improved detonator system which is safe and reliable and
insensitive to shock, radio waves and heat for initiating a main charge
of insensitive explosives.

BRIEF SUMMARY OF THE INVENTION

[0023] The present inventor conducted extensive experimentations, and
unexpectedly discovered a detonator which achieves the foregoing
described objects of the present invention. The detonator of the present
invention eliminates the need for lead azide and/or lead staphynate by
employing a detonator train comprising a plurality of insensitive
energetic segments, each of which is formed by compacting powder or
granules of an insensitive energetic. A first segment in the detonation
train of the insensitive energetic is compacted under a pressure which is
low enough to facilitate initiation of the first segment by a shock cord
or fuse. Additional segments in the detonation train are compacted under
pressures higher than the pressures used in compacting the first segment
since these additional segments are designed so as not to detonated by
the shock cord or fuse, but instead only by segments of insensitive
explosive in the detonation train.

[0024] The last segment of insensitive energetic in the detonation train
is compacted to a high enough pressure that it will not be detonated by
the shock cord or fuse, but instead only by detonation of a next to the
last segment of insensitive energetic in the detonation train.

[0025] In this scenario, the last segment compacted under the highest
pressure is the toughest segment to initiate. This difficult to initiate
property is ideal in cases where insensitive munitions are desired. Using
RDX as an example, varying the pressing forces in terms of psi can
produce an energetic segment that does not initiate from the stimuli of a
primer as in the case of a grenade fuse assembly into a detonator
assembly capable of using only an RDX energetic with differing
laminations or presses of the energetic.

[0026] In this case, the normal or ideal RDX pressing pressure of about
4,000 psi produces a last segment in a detonator train which is difficult
to initiate and, therefore, requires that other energetic materials be
used to initiate it in a detonator assembly. To achieve the objects of
the present invention, other segments of RDX (or other insensitive
energetic) are used which have been compressed to a pressure of less than
about 4,000 psi and which, when initiated, produce an explosion
sufficient to initiate the last segment in the train.

[0027] By employing a detonator train of insensitive energetic segments
which have been compressed under diminishing compression forces, the
detonator of the present invention produces a sequence of detonations
proceeding from a first segment compacted under the lowest pressure to
the last segment compacted under the highest pressure.

[0028] In a first preferred embodiment of the present invention there is
provided in an explosive pyrotechnic device, military munition, or rocket
comprising:

(a) a main charge of explosive or propellant formed primarily of an
insensitive energetic composition; (b) a detonator to trigger or initiate
the main charge, said detonator being primarily formed of an insensitive
energetic composition, lead azide, and lead styphnate; (c) a fuse, shock
cord or primer to trigger or initiate the detonator; the following
improvement comprising: a detonator formed entirely from a plurality of
discrete segments of an insensitive energetic composition, each segment
being formed by compacting under pressure powdered or granular
insensitive energetic composition having a sensitivity to detonation
which decreases with an amount of compressive force applied in compaction
of the powder or granules of the insensitive energetic composition, said
plurality of discrete segments comprising at least a first and last
discrete segment of compacted insensitive energetic composition, each
having been formed under different compaction pressures: said first
segment being compacted under a compaction pressure low enough that
ignition of the fuse or primer will effect detonation of said first
segment without detonating either the main charge or any other segment of
the insensitive energetic composition, said last segment being subjected
to a compaction pressure high enough that only ignition of another
segment will initiate detonation of said last segment, which in turn
initiates detonation of said main charge, thereby eliminating the need in
the detonator for lead azide and lead styphnate.

[0029] In a second preferred embodiment of the present invention there is
provided in connection with the first preferred embodiment a detonator
wherein the plurality of segments employed in the detonator are each
compacted under different pressures from powder or granules of
insensitive energetic composition so as to form an energetic train which
sequences detonation of the individual segments starting with the segment
produced under the lowest compaction pressure, and then progress to
segments compacted under higher compaction pressures.

[0030] In a third preferred embodiment of the present invention there is
provided in connection with the first preferred embodiment a detonator
formed from granules and/or powdered RDX.

[0031] In a fourth preferred embodiment of the present invention there is
provided in connection with the first preferred embodiment a detonator
formed from granules and/or powdered HMX.

[0032] In a fifth preferred embodiment of the present invention there is
provided in connection with the third preferred embodiment a detonator in
which the first segment is compacted under a pressure of about 2,000 psi.

[0033] In a sixth preferred embodiment of the present invention there is
provided in connection with the third preferred embodiment a detonator in
which the last segment is compacted under a pressure of about 4,000 psi.

[0034] In a seventh preferred embodiment of the present invention there is
provided in connection with the third preferred embodiment a detonator in
which the first segment is compacted under a pressure of about 2,000 psi,
and the last segment is compacted under a pressure of about 4,000 psi.

[0035] In an eighth preferred embodiment of the present invention there is
provided in connection with the first preferred embodiment an explosive
pyrotechnic device selected from the group consisting of hand grenades,
bombs, rockets, mortars, mines, satchel charges, bazooka shells,
artillery shells, destructor assemblies, and ammunition. In a ninth
preferred embodiment of the present invention there is provided in
connection with the first preferred embodiment an explosive pyrotechnic
device having an explosive charge used in rock blasting, mining, and/or
oil drilling.

[0036] In a tenth preferred embodiment of the present invention there is
provided a detonator formed entirely from a plurality of discrete
segments of an insensitive energetic composition, each segment being
formed by compacting under pressure powdered or granular insensitive
energetic composition having a sensitivity to detonation which decreases
with an increase in the amount of compressive force applied in compaction
of the powder or granules of the insensitive energetic composition, said
plurality of discrete segments comprising at least a first and last
discrete segment of compacted insensitive energetic composition, each
having been formed under different compaction pressures.

[0037] In an eleventh preferred embodiment of the present invention there
is provided in connection with the tenth preferred embodiment a detonator
in which said first segment is compacted under a compaction pressure low
enough that ignition of the fuse or primer will effect detonation of said
first segment without detonating either the main charge or any other
segment of insensitive energetic composition.

[0038] In a twelfth preferred embodiment of the present invention there is
provided in connection with the tenth preferred embodiment a detonator in
which said last segment is subjected to a compaction pressure high enough
that only ignition of a next to the last segment will initiate detonation
of said last segment, which in turn causes detonation of the main charge.

[0039] In a thirteenth preferred embodiment of the present invention there
is provided in connection with the tenth preferred embodiment a detonator
in which the plurality of segments employed in the detonator are each
compacted at different pressures from powder and/or granules of
insensitive energetic composition so as to form an energetic train which
sequences detonation of the individual segments starting with the first
segment produced with the lowest compaction pressure and then progressing
to a last segment compacted at a highest compaction pressure.

[0040] In a fourteenth preferred embodiment of the present invention there
is provided in connection with the tenth preferred embodiment in which
said first segment is compacted under a compaction pressure low enough
that ignition of the fuse or primer will effect detonation of said first
segment without detonating either the main charge or any other segment of
the insensitive energetic composition, and said last segment being
subjected to a compaction pressure high enough that only ignition of a
next to the last segment will initiate detonation of said last segment,
which in turn causes detonation of said main charge.

[0041] In a fifteenth preferred embodiment of the present invention there
is provided in connection with the fourteenth embodiment a detonator in
which the plurality of segments employed in the detonator are each
compacted at different pressures from powder and/or granules of
insensitive energetic composition so as to form an energetic train which
sequences detonation of the individual segments starting with the segment
produced under the lowest compaction pressure and then progressing to
segments compacted under increasingly higher compaction pressures.

[0042] In a sixteenth preferred embodiment of the present invention there
is provided in connection with the tenth preferred embodiment a detonator
formed from granules and/or powdered RDX.

[0043] In a seventeenth preferred embodiment of the present invention
there is provided in connection with the sixteenth preferred embodiment a
detonator in which the first segment of RDX is compacted under a pressure
of about 2,000 psi, and the last segment of RDX is compacted under a
pressure of about 4,000 psi.

[0044] In an eighteenth preferred embodiment of the present invention
there is provided in connection with the tenth preferred embodiment a
detonator which is formed from granules and/or powdered HMX.

[0045] In a nineteenth preferred embodiment of the present invention there
is provided in connection with the tenth preferred embodiment a
pyrotechnic device selected from the group consisting of hand grenades,
bombs, rockets, mortars, mines, satchel charges, bazooka shells,
artillery shells, destructor assemblies, and ammunition.

[0046] In a twentieth preferred embodiment of the present invention there
is provided a detonator formed entirely from a plurality of discrete
segments of an insensitive energetic composition, each of said segments
employed in the detonator being compacted at different pressures from
powder and/or granules of insensitive energetic composition so as to form
an energetic train which sequences detonation of the individual segments
starting with a first segment in the detonation train produced under the
lowest compaction pressure, and then progresses to segments compacted
under higher compaction pressures until a last segment in the detonation
train is initiated by a next to the last segment, and a main charge is
initiated only by detonation of the last segment.

[0047] Further areas of applicability of the present invention will become
apparent from the detailed description provided hereinafter. It should be
understood that the detailed description and specific examples, while
indicating preferred embodiments of the present invention, are intended
for purposes of illustration only and are not intended to limit the scope
of the invention.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0048] Additional advantages and features of the present invention will
become apparent from the subsequent description and appended claims,
taken in conjunction with the accompanying drawings, wherein:

[0049]FIG. 1 is a cross-sectional view of a conventional explosive
device, illustrating particularly a conventional detonator used in a
prior art detonation chain.

[0050]FIG. 2 is a cross-sectional view of a conventional detonator,
illustrating particularly the position of the conventional items used in
the conventional detonator chain.

[0051]FIG. 3 is a cross-sectional view of a conventional hand grenade,
illustrating particularly the components of the detonator assembly.

[0052]FIG. 4 is a cross-sectional view of a detonator of the present
invention, illustrating particularly the use of multiple segments of
compacted RDX replacing the lead azide and lead styphnate used in
conventional detonators.

[0053]FIG. 5 is a cross-sectional view of a hand grenade made according
to the present invention which employs a detonator having multiple
segments of compacted RDX replacing the lead azide and lead styphnate
used in conventional hand grenades.

[0054]FIG. 6 is a cross-sectional view of an explosive device of the
present invention in which a high order RDX mix main charge is initiated
by a lower order segment of RDX, and a burn mix segment of RDX, in which
the burn mix can be made with additional laminations at lower compaction
pressures, such that either a shock cord or fuse can initiate the burn
mix.

DETAILED DESCRIPTION OF THE INVENTION

[0055] In a preferred embodiment of the present invention there is shown
generally at 41 in FIG. 4 a detonator train comprising shock cord 43,
burn mix 45 of RDX compacted under a pressure of about 2,000 psi, low
order mix 47 of RDX compacted under a pressure of about 3,000 psi, and
high order mix 49 of RDX compacted under a pressure of about 4,000 psi.

[0056] In FIG. 4, the high order mix 49 is the energetic segment at the
desired compaction or pressing force pressure, in this case RDX compacted
at a pressure of approximately 4,000 psi. At this pressure of compaction,
it would be nearly impossible to initiate the RDX with shock cord 43 on a
consistent basis. The next level of energetic compaction of RDX segments
is the low order mix segment 47, which is approximately 1/3 to 1/2 less
in compaction pressure as the high order mix compaction segment 49. This
may or may not be enough for shock cord 47 to initiate the reaction,
because the compaction of the energetic needs not only the energetic but
also binders which are used to aid the compaction process so that the
energetic does not react during pressing. These binders also maintain the
compacted powder or granules after pressing and bond together the
ingredients in the pressed segments.

[0057] Where further initiation improvements are desired, a third, fourth
or more segments such as burn mix 45 may be included until the desired
energetic train reaction is achieved. Each type of energetic chosen (such
as RDX, Composition A-5, or HMX) for a particular type of detonator may
require tailoring and adjustment of the number of segments of a
particular energetic in the detonator train for the particular main
charge to be detonated. The burn mix 45 compaction may be 1/3 to 1/2 less
in compaction pressure as the previous segment. This general formula may
not be ideal for all types of energetic, and needs to be evaluated and
adjusted for each application as are current energetic mix methods,
technology and industrial standards for explosive materials.

[0058] In accordance with the present invention, the previously used
primary energetics (lead styphnate and/or lead azide) are eliminated and
these primary energetic are replaced by detonating energetic high order
mix segments, except these segments are compacted to a lower pressing
pressure than the high order mix. In the detonator train of the present
invention, a high order mix can be initiated using the same type of
energetic materials as in the other segments of the detonator train,
except produced at lower compaction pressures. In such cases, these high
order mixes need large stimuli to initiate as is currently used with lead
styphnate and lead azide as primary energetic. The low order and burn mix
segments used in the detonator train of the present invention are used to
replace the primary energetic of lead styphnate and lead azide, which
results in a more insensitive munition (IM) energetic.

[0059] Detonators employing the use of the same type of high order
energetic segments throughout the detonation train can be used in most
detonator systems, fuse systems and military systems including destructor
assemblies, grenades, mortars, military ammunition including artillery
shells, mines, bombs, rockets and torpedos, etc.

[0060] In another preferred embodiment of the present invention as
illustrated in FIG. 6 is a detonator shown generally at 70 which
comprises shock and/or fuse 73, burn mix 75 of RDX compacted under a
pressure of about 2,000 psi, a low order mix 77 of RDX compacted under a
pressure of about 3,000 psi, and a high order mix 79 of RDX compacted
under a pressure of about 4,000 psi. Optionally, the burn mix can be made
with additional laminations or segments at lower compaction pressures,
such that either a shock cord or fuse can initiate the burn mix.

[0061] Although any insensitive energetic composition can be employed in
the detonator of the present invention, when their sensitivity to
detonation decreases with an increase in the amount of pressure applied
during compaction of powders and/or granules of the insensitive
energetic, it is preferred to employ granular or powdered energetic
compositions selected from the group consisting of RDX, HMX, Composition
A-3, Composition A-5, LX-04, LX-07, LX-09, LX-10, LX-11, LX-14, LX-15,
LX-16, LX-17, PBX-9007, PBX-9010, PBX-9011, PBX-9205, PBX-9404, PBX-9407,
PBX-9501, PBX-9502, PBX-9503, PBX-9604, PBXN-5, AFX-601, AFX-902,
AFX-511, AFX-521, PAX-2A, PAX-3, PAX-30, PAX-50, PBXN-9.

[0062] Powder and/or granules of the insensitive energetic composition are
commonly available industrially. These materials can be compacted in a
die cavity filled with the energetic composition, by a mandrel which
forces the powdered and/or granule insensitive composition into the die
cavity under pressure. The pressure of compaction can be varied by
adjusting the travel of the mandrel, and measuring the pressure of
compaction. These compaction steps can be repeated for a second and third
pressing to produce a burn mix which is the easiest to ignite.

[0063] In the present invention, the first segment of granular or powdered
insensitive energetic is compacted to the lowest pressure which will
produce a segment which can be initiated by the fuse or detonation cord
to be used. The next segments of granular and/or powdered insensitive
energetic are compacted under higher pressure which will produce one
segment which can be initiated by detonation of the first segment. This
process continues until a last segment of granular and/or powdered
insensitive energetic is compacted under a pressure which will produce
the last segment capable of initiation by the next to the last segment in
the detonation train.

[0064] The size and compaction of the last segment is designed to initiate
detonation of a main charge of insensitive energetic. However, the last
segment in the detonation train is only initiated by detonation of a next
to the last segment in the detonation train, and detonation of the next
to the last segment is insufficient to initiate detonation of the main
charge. Thus, this detonation train sequences detonation of these
segments of insensitive energetic from a first segment having the lowest
amount of compaction to a last segment having the highest amount of
compaction. Therefore, detonation of the main charge can be achieved
without the use of lead azide, and/or lead styphnate, or any other
sensitive energetic material.

[0065] Detonators produced according to the present invention can also be
used in police, SWAT, and other law enforcement activities. Additionally,
the detonators of the present invention can be used in construction, rock
blasting, mining, and oil drilling applications that can benefit from the
use of less sensitive energetics. The detonators of the present invention
are also less sensitive to radio waves, cell phones, microwaves and other
frequencies that may initiate detonation of energetics of conventional
explosives used in these fields. The use of conventional detonators
exposes the users to great danger such as from an undesired initiation of
explosives by radio waves.

[0066] The industry has made great strides in the undesired explosion area
with the use of flying disk initiators that require high voltages to
initiate an explosive, but this too may benefit from a less reactive
energetic initiation detonator as described above.

[0067] It is to be understood that the present invention is not to be
limited to the specific embodiments disclosed herein, but is intended to
cover such variations as are traditional within the field of the
invention. In addition, many modifications may be made to adapt a
particular situation or material to the teachings of the invention
without departing from the essential scope thereof. It is intended that
the invention not be limited to the particular embodiments illustrated by
the drawings and described in the specification as the best mode
presently contemplated by this invention, but that the invention will
include any embodiments falling within the foregoing description and
appended claims.